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1.
不同氮肥对大豆根圈土壤酶活性和氮营养分布的影响 总被引：3，自引：0，他引：3
氮是植物生长最重要的营养元素。本文报道了利用根箱系统，5种不同的氮肥(硝酸钠、硫酸铵、尿素、LP-40和LP-70)处理对典型黑土条件下生长的大豆根圈3种土壤酶活性及NO3^--N和NH4^ -N含量分布的影响。结果表明，除了长效缓释氮肥LP-70处理的亚硝酸还原酶活性表现为根圈亏缺外，其它氮肥处理的硝酸还原酶、亚硝酸还原酶和尿酶活性在根圈土壤中要大于非根圈土壤。对NO3^--N含量在大豆根圈分布结果证明，当硫酸铵、尿素、LP—40和LP—70处理时，它在大豆根圈表现为亏缺效应，而当供给硝酸钠处理时，NO3^-—N含量在大豆根图表现为强烈的累积效应。不同氮肥对NH4 ^ —N含量分布的影响结果为；当供给硫酸铵处理时，NH4^ —N在根面区少量累计，而当其它4种氮肥处理时，NH4^ —N表现为亏缺。本试验结果证明不同氮肥对大豆根圈土壤酶活性及氮营养状况影响很大。 相似文献
2.
不同茬口种植的大豆品种根渗出物对大豆孢囊线虫卵孵化的影响 总被引：8，自引：1，他引：8
取北方5种作物轮作茬口和休闲土壤种植不同大豆品种,出苗后22d制备植株的根渗出物观察对大豆孢囊线虫(SCN)卵孵化的影响.试验结果表明,同一品种在不同茬口土壤种植后获得的根渗出物对SCN卵孵化率不同,抗线3号在不同的茬口条件下根渗出物对SCN卵孵化率差异很大,豆麦米轮作、米豆米迎茬和豆麦豆迎茬条件下对SCN卵孵化具有促进作用,但在麦豆麦迎茬、连作12a大豆和休闲条件下根渗出物对SCN卵孵化具有抑制作用.合丰25只在连作12a大豆条件下对SCN卵孵化具有促进作用,而在豆麦米轮作、麦豆麦迎茬、米豆米迎茬和豆麦豆迎茬条件下均表现为对SCN卵孵化的抑制作用,在休闲条件下与对照差别不大.抗线4号在6个茬口中没有明显的促进或抑制作用,基本与对照差别不大. 相似文献
3.
为探究关中平原地区不同作物茬口对冬油菜养分积累和产量的影响,通过两年田间试验,研究分析不同
茬口,包括休闲茬口（FW）、大豆茬口（SW）、毛苕子茬口（HW）和玉米茬口（MW）对冬油菜土壤养分含量、地上部干
物质积累、分配和氮磷养分吸收积累、产量构成因素以及产量的影响,筛选冬油菜生产适宜的前茬作物,为加强冬
油菜生产,提高土地利用效率提供理论依据。结果表明：与休闲茬相比,大豆茬、毛苕子在冬油菜关键生育时期土
壤碱解氮、硝态氮、铵态氮、速效磷含量均显著提高,其中以大豆茬提升土壤养分效果最为明显,而玉米茬各土壤养
分含量均有所下降;大豆茬、毛苕子茬冬油菜地上部干物质积累量较休闲茬分别提高26.05%、13.12%,玉米茬下降
2.74%;氮素积累量较休闲茬分别提高30.86%、14.86%;磷素积累量较休闲茬分别提高37.03%、20.35%,玉米茬氮、
磷素积累量较休闲茬降低12.76%、3.48%;与休闲茬相比,大豆茬、毛苕子茬冬油菜籽粒产量显著提高29.48%、
17.77%,玉米茬与休闲茬冬油菜产量差异不显著。相关性分析结果表明,大豆茬、毛苕子茬增产归因于土壤养分、
地上部干物质积累量、氮磷养分积累量以及单株角果数的增加。因此,在关中平原地区,大豆、毛苕子是冬油菜生
产适宜前茬作物,而大豆是提高冬油菜籽粒产量、氮磷养分积累的理想前茬作物。 相似文献
4.
为了解不同土地利用方式对土壤线虫垂直分布的影响,对中国科学院海伦生态农业实验站长期定位试验区大豆田0—80cm深度土壤线虫进行研究,所取土样茬口为大豆连作15a、麦-米-豆轮作、麦豆麦豆迎茬和休闲地,以期明确不同土地利用方式下土壤线虫总数和营养类群的变化。结果表明：各取样田土壤线虫总数从0—5到60—80cm深度呈现逐渐下降趋势,0—30cm耕层土壤是线虫主要的聚集地。各营养类群线虫在取样茬口间数量动态变化有差异,总的来说大豆田高于休闲田,而大豆不同茬口营养类群变化不同,捕食杂食类群出现最少。 相似文献
5.
大豆胞囊线虫(Heterodera glycines Ichnohe,简称SCN)病是一种大豆最严重的病害之一,应用抗病品种和轮作是控制该病最经济有效的方法.上个世纪80年代以来我国也相继育成了一些抗大豆胞囊线虫病品种,为了探讨不同抗性品种与大豆胞囊线虫群体动态关系和抗性品种的抗性机制,在黑土区的中国科学院海伦农业生态试验站的长期定位区,取我国大豆主产区常见的小麦--玉米--大豆轮作、玉米--大豆--玉米--大豆迎茬、小麦--大豆--小麦--大豆迎茬和大豆连作13年4种轮作方式,以在我国大豆主产区育成的抗大豆胞囊线虫3号生理小种的抗线4号和非抗病品种黑农35为材料,研究了不同抗性品种大豆在不同轮作系统中根内不同龄期线虫和根面雌虫发育动态.结果表明,不同大豆品种根内二龄幼虫(J2)数量存在着差异,在大豆连作13年、豆米豆和豆麦豆茬口上种植的抗线4号根内J2数量高于黑农35;在大豆连作13年、轮作、米豆米豆迎茬和麦豆麦豆迎茬4个茬口中抗线4号根内三龄幼虫(J3)、四龄幼虫(J4)数量和根面雌虫数量明显低于黑农35.由此推断抗线4号对大豆胞囊线虫3号生理小种的抗性机制可能是抗线虫发育,而不是抗线虫侵入. 相似文献
6.
不同作物茬口对连作大豆产量及农艺性状的影响 总被引：7，自引：2，他引：5
为利用轮作换茬措施缓解连作大豆的危害和产量损失,研究了苜蓿、玉米和大豆3种作物茬口对连作大豆产量和农艺性状的影响.结果表明:苜蓿茬3年连作大豆比玉米茬3年连作大豆增产10.4%,比4年连作大豆极显著增产26.7%;玉米茬3年连作大豆比4年连作大豆显著增产14.7%.与4年连作大豆相比,苜蓿茬和玉米茬连作3年大豆的株高分别增加16.6 cm和14.7 cm、单株粒重分别增加7.0 g和3.7 g,差异均达极显著;苜蓿茬和玉米茬处理间的株高、单株粒重差异不显著.4年连作大豆的病粒率分别比苜蓿茬和玉米茬3年连作大豆的病粒率高4.54%和6.74%,差异达显著和极显著;苜蓿茬、玉米茬处理间的病粒率差异不显著.三个茬口处理之间大豆虫食粒率差异不显著.可见,对于连作大豆,苜蓿茬口优于玉米茬口和大豆茬口. 相似文献
7.
不同形态氮肥对大豆根系形态及磷效率的影响 总被引：1，自引：0，他引：1
采用框栽试验方法,研究生物固氮(CK),NO-3-N,NH+4-N,Glycin-N,Protein-N和Urea-N 6种不同形态氮素对大豆各生育时期根系生物量、根冠比、根系形态及磷效率的影响.结果表明:不同形态N处理对大豆根系生物量、根系形态特征(根长、根体积、根表面积及根尖数等)及磷吸收、利用效率影响不同,随着生育期的推进,NO-3-N和Protein-N均显著高于其它处理,但二者之间差异不显著;Glycin-N,Urea-N和NH+4-N均高于CK(生物固氮),但Glycin-N、Urea-N和NH+4-N处理间差异不显著.不同形态N处理的根干重、根长、根体积、根表面积均高于CK,而根冠比、平均直径以及磷利用效率则低于CK. 相似文献
8.
为从线虫生态角度评价土壤健康状况和大豆轮作系统的合理性及预测大豆根部病害发生与为害,利用浅盘法收集大豆不同轮作系统下苗期、花期和结荚期土壤线虫,研究大豆不同生育期土壤总体线虫和重要属植物线虫群体动态.取大豆连作14年、小麦-玉米-大豆轮作、麦豆麦豆迎茬、米豆米豆迎茬和休闲区0～20 cm土壤.结果表明:土壤中胞囊线虫密度为迎茬(米豆、麦豆)轮作连作休闲;从大豆苗期、花期至结荚期,各轮作系统胞囊线虫密度逐渐递增,麦豆迎茬和轮作土壤中总体线虫密度呈递增趋势,各轮作系统苗期和花期土壤总体线虫差异显著;3个时期,轮作土壤中总体线虫密度分别最大,而休闲土壤中螺旋-盘旋-拟盘旋线虫为优势种群. 相似文献
9.
氮素形态对大豆根系形态性状及释放H+的影响 总被引：3，自引：0，他引：3
采用水培培养方法,研究了不同形态氮素对大豆根系形态性状及释放H 的影响.结果表明,不同形态氮素对根系形态特性的影响不同,表现为,NO3-N和NH4NO3-N促进根表面积增加;NH4 -N对根系的生长表现出抑制作用;而生物固氮处理,除根尖数随生育期的延长而增加外,其他根系形状几乎没有变化.NH4 -N处理根系释放出大量H ,且大豆根系受到NH4 -N的毒害,阻碍了根系对其它元素的吸收;而NO3-N处理,根系释放出大量OH-,对根系吸收其他元素的抑制作用较小,因此,生物量增加较明显;NH4NO3-N处理根际pH变化较小,促进大豆植株生长;而生物固氮处理,在生育前期,根瘤固氮能力较弱,不能及时为大豆生长提供充足的氮素,进而抑制大豆的生长,使生物量偏低. 相似文献
10.
不同作物茬口与施肥对连作大豆产量的影响 总被引：3，自引：0，他引：3
采用2因素有重复完全随机试验,研究苜蓿、玉米和大豆3种茬口与施肥对连作大豆产量的影响.3 a的试验结果表明:苜蓿茬口上连作3 a的大豆产量都显著或极显著高于玉米和大豆茬口上相应连作年份的大豆产量;不同年份,施肥对不同作物茬口上连作大豆的产量影响效果不同;在每公顷施二铵180 kg、尿素45 kg、氯化钾45 kg(C2)肥量以下时,各茬口连作大豆产量与相应茬口不施肥处理连作大豆产量间差异不显著;即使苜蓿茬口上不施肥,其连作1、2、3 a大豆产量也高于所有玉米茬与施肥水平组合的对应年份连作大豆产量,而全部显著或极显著高于大豆茬与各施肥水平组合的对应年份连作的大豆产量.苜蓿茬上施大豆专用复合肥375 kg·hm-2组合处理大豆产量最高(2911.5 kg·hm-2),显著或极显著的比其它21个组合增产0.57%～54.42%.可见在连作大豆情况下,相对玉米和大豆茬而言,苜蓿茬起到了增产、增效、环境友好型和降低施肥成本的作用. 相似文献
11.
12.
黑土区不同轮作系统大豆根际镰孢菌种群结构和数量 总被引：2，自引：0，他引：2
对中国科学院海伦农业生态试验站长期定位区大豆连作17年、小麦-玉米-大豆轮作、玉米-大豆迎茬和大豆连作2年,分别取分枝期、花期和鼓粒期的大豆根际土壤,采用土粒平板法进行镰孢菌分离,探讨大豆连作对镰孢菌种群结构和数量的影响.根据形态学特征鉴定出6种镰孢菌,即锐顶镰孢(F.acuminatum Ellis ＆ Everhart)、黄色镰孢(F.culmorum(W.G.Smith)Saee.)、木贼镰孢(F.equiseti(CoMa)Saec.)、禾谷镰孢(F. graminearum Schwabe)、尖孢镰孢(F. oxysporum Schleeht.)和腐皮镰孢(F. solani(Mart.)Sacc.).在不同生育期及不同轮作系统大豆根际土壤中尖孢镰孢(F. oxysporum)数量较高,与其它种类相比差异显著(P＜0.05),是大豆根际土壤中的优势菌.不同轮作系统大豆根际土壤以尖孢镰孢数量平均值最高,其次为腐皮镰孢;不同轮作系统镰孢菌总量动态变化一致,花期轮作镰孢菌数量最高为1.54 x 104个·-1干土,与大豆连作17年相比差异明显.在3个生育期大豆连作17年尖孢镰孢数量均略低于轮作. 相似文献
13.
Sudden death syndrome, caused by Fusarium virguliforme, and the soybean cyst nematode, Heterodera glycines, combined cause the highest yield losses in soybean. The objective of this study was to determine the effectiveness of corn rotated annually with soybean on reducing severity of sudden death syndrome (SDS) and if such crop rotation is beneficial to soybean root health and thus improves disease management strategies. Experiments were conducted from 2003 to 2006 through two cycles of a corn–soybean rotation on two commercial fields in Indiana. With one exception, the rotation of soybean with corn did not provide yield benefits compared to monoculture of soybean. Severity of foliar and root symptoms of SDS in rotation plots were never less than in soybean monoculture plots. At one location, soybean monoculture resulted in suppression of SDS compared to the corn–soybean rotation, while H. glycines reproduced freely. At the other location, monoculture of soybean resulted in suppressiveness against H. glycines, while SDS was limited in all treatments. The data suggest that soil suppressiveness can independently impact the pathogens that are important in SDS development. Because H. glycines can increase SDS symptoms, its suppression may also reduce severity of SDS. Current production systems consisting of yearly rotation of soybean with corn are highly vulnerable to the development of severe soil-borne disease complexes. The simple year-to-year rotation of corn and soybean is not considered sustainable. While monoculture of soybean resulted in some disease suppression in these trials, reliance on monoculture may be detrimental due to other environmental considerations beyond the scope of these trials. Including other crops may be beneficial in improving the sustainability of soybean and corn production systems. 相似文献
14.
以土壤线虫为指示生物,研究了大豆不同耕作系统土壤线虫群落结构、生态指数和食物网指数的变化特征,以期明确大豆长期连作对土壤生物多样性和土壤食物网结构的影响。结果表明:大豆轮作土壤线虫属最丰富,大豆长期连作25年后土壤线虫属水平种类最少。大豆轮作和大豆短期连作3年土壤线虫群落组成Jaccard相似性最高(0.81),大豆轮作和大豆长期连作25年Jaccard相似性最低(0.66)。大豆短期连作3年土壤中植物寄生线虫的数量最高,显著高于大豆轮作和大豆长期连作25年。食真菌线虫在大豆长期连作25年土壤中较丰富,显著高于大豆轮作和大豆短期连作3年。大豆长期连作25年植物寄生线虫成熟度指数(PPI)高于大豆短期连作3年和大豆轮作。土壤线虫的通路指数(CI)在3个处理中均小于50,土壤腐蚀食物网的降解以细菌降解通路为主。大豆短期连作3年处理位于富集指数(EI)和结构指数(SI)食物网特征图的A象限,大豆轮作和长期连作25年位于食物网特征图的B象限。结果表明,大豆长期连作改变了土壤线虫的群落结构,降低了属的多样性,食物网结构向成熟稳定的方向恢复。 相似文献
15.
《中国油料作物学报(英文)》2020,5(3):149-155
Through collecting rhizosphere soil sample from a 30-year long-term fixed location test site that use “rice-rice-rape” crop rotation (RRR) and “rice-rice-fallow” continuous cropping systems (RRF), this paper investigated effects of long-term crop rotation on physicochemical property and bacterial community of rhizosphere soil. Results showed that total nitrogen (TN), total phosphorus (TP) and available potassium (AK) contents in rhizosphere soil under long-term RRR were decreased by 28.09%, 15.69% and 6.25% respectively. Alkali-hydrolyzable nitrogen (AN) and available phosphorus (AP) contents were 10.59% and 13.25% higher than those of soil in RRF respectively. Three soil samples collected during different periods also showed that RRR resulted in a lower rhizosphere soil pH than RRF. Clone library analysis revealed that significant difference in rhizosphere soil bacterial community was observed between RRR and RRF continuous cropping. Abundance of α-Proteobacteria, β-Proteobacteria and γ-Proteobacteria were higher in rhizosphere soil of RRR compared to RRF. pH of rhizosphere soil was significantly correlated with Acidobacteria level, while total organic carbon (TOC) content was significantly correlated with Proteobacteria level. Long-term RRR enhanced conversion of N and P in rhizosphere soil, increased bio-availability to crop, and promoted diversity of soil bacterial community. Bacterial diversity in RRR could be ecological significance in maintaining soil fertility and functionality. 相似文献
16.
铝胁迫下大豆根系分泌物对根际土壤的影响 总被引：1，自引：2，他引：1
以2个大豆品种（浙春2号和浙春3号）为材料，设置了4个铝浓度，分别在铝处理7d和14d时，测定大豆根系分泌物中的氨基酸、有机酸及可溶性糖，同时对大豆根际土壤的pH值、土壤酶和土壤呼吸速率进行分析。实验结果显示，虽然根系分泌物对根际土壤具有一定的酸化作用，但是随着铝浓度的升高，根系分泌物有使根际土壤酸碱度趋向平衡的效应。低铝浓度下，大豆根系分泌较多的可溶性糖和氨基酸，促使根际土壤酶活性的增强和土壤呼吸速率的提高，同时还可分泌较多的柠檬酸，与大豆的耐铝性相关。高铝浓度抑制主要根系分泌物的分泌，降低土壤酶活性和土壤呼吸速率；但高铝胁迫增加可溶性糖分泌量。实验结果表明，浙春2号大豆比浙春3号大豆耐铝；随着铝处理时间的延长，铝毒害作用明显。 相似文献
17.
The effects of tillage on Heterodera glycines, the most important yield-reducing pathogen of soybean in the U.S., were examined in a long-term tillage and crop sequence study initiated in 1975 on a mollisol at Purdue University. Population densities of H. glycines were monitored under corn–soybean rotation and soybean monoculture in 2003 and 2004. Tillage treatments included: (A) fall moldboard plow + spring secondary tillage; (B) fall chisel plow + spring secondary tillage; (C) ridge tillage; and (D) no-tillage. In both years in the rotational plots, final population densities of H. glycines were proportional to tillage intensity. Under both soybean and corn rotation crops, highest population densities were observed with plowing + secondary tillage and lowest population densities were detected under no-tillage. In 2004, population densities in monoculture soybean soil declined with depth intervals in layers of 0–10, 10–20, and 20–30-cm depth under no-till, but not in plowed plots. Multiple regression analysis determined that the stratification of nematode population densities was strongly correlated to penetrometer resistance and potassium concentration of the soil. Tillage seemed to affect population densities of H. glycines by modification of the soil physical parameters in corn–soybean rotation plots. Reducing tillage intensity was beneficial in reducing population densities of H. glycines in rotational soils. Thus, the choice of tillage system can reduce the risk for damage by this widely distributed pathogen. 相似文献
18.
长期轮作和连作对土壤中 大豆胞囊线虫数量的影响 总被引：13，自引：0，他引：13
在白浆土设计长期轮作和连作试验区,采取麦麦豆油玉豆6区轮作和麦玉豆连作, 18a内连续调查土壤 中大豆胞囊线虫( SCN)的胞囊数量,观察轮作或连作对土壤中SCN胞囊数量的影响。试验结果表明,长期轮作使 土壤中胞囊数量有减少的趋势,各茬口间胞囊数量变化幅度减小,轮作12a后土壤中胞囊数量达到动态平衡;大豆 连作的前2a土壤中胞囊数量急速增加,以后缓慢增加, 7a后有下降趋势, 14a后土壤中的胞囊数量在较高水平上趋 于平衡;小麦或玉米连作前3a土壤中的胞囊数量呈快速下降, 4a后缓慢减少, 14a后土壤中胞囊数量极少。 相似文献
19.
Adriana Pereira Silva Letícia Carlos Babujia Julio Cezar Franchini Rosinei Aparecida Souza Mariangela Hungria 《Field Crops Research》2010
Management and cropping systems varying in soil mobilization rates and plant-residue inputs may have profound effects on the biological properties of soil. Therefore, the objective of this study was to quantify soil microbial biomass carbon and nitrogen (MB-C and MB-N)—by means of the fumigation-extraction method—under varied soil-management and crop-rotation/succession systems in southern Brazil, correlating the results with yields of soybean and maize crops. The microbial biomass and grain yields were examined at the 0–10 cm layer in four short- to long-term field experiments. Experiment 1 was a 26-year trial consisting of four soil-management systems: (1) no-tillage (NT), (2) conventional tillage [(CT) with disc plough], (3) field cultivator (FC) or (4) heavy-disc harrow (DH), each with a crop succession (CS) of soybean (summer) and wheat (winter). Experiment 2 was a 21-year trial consisting of one CS, soybean/wheat every year) and seven crop rotations (CRs) comprising soybean, maize, wheat and green manures (lupine, radish and black oat), under the NT system. Experiment 3 comprised a 14-year CT trial, and 4-year and 14-year NT trials, with both one CS and two CRs. Experiment 4, a 10-year trial consisted of CT and NT and three CRs. Analyses were performed during the summer and winter croppings. Differences in microbial parameters, as a function of crop succession and rotation, were not easily detected as they varied as a function of a complex combination of plant species and time of implementation of the experiment. In contrast, MB-C and MB-N values were consistently higher—up to more than 100%—under NT in comparison to CT and were associated with higher grain yields. Our results—from this wide range of experiments—suggest that MB-C and, particularly, MB-N are sensitive indicators of the effects of soil- and crop-management regimens. 相似文献